To identify alcoholism risk genes, we are collecting and testing for linkage families from three American Indian populations which are relatively homogeneous and in which alcoholism is highly prevalent. This study also addresses the genetic epidemiology and psychiatric comorbidity of alcoholism in Indians. Two hundred Cheyenne Indians have been clinically evaluated and their cell lines immortalized. At Jemez Pueblo, data and cell lines have been collected for 100 subjects. A study on the Pima Indians is in progress. A large panel of random polymorphic probes has been typed in Cheyenne alcoholics and controls and genetic linkage analysis is in progress for this group.